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15.992 S-Lab: Laboratory for Sustainable Business
Spring 2008
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Ecological and
Economic Sustainability
John Sterman
S-Lab
7 Feb 2008
What is sustainability?
What is sustainable development?
Brundtland Commission (1987):
“Sustainable development is
development that meets the needs of
the present without compromising the
ability of future generations to meet
their own needs.”
http://www.un-documents.net/wced-ocf.htm
A Finite Planet
Insolation
(Solar energy)
High-Grade Natural
(Low Entropy) Capital
Stocks
Resources
Natural
Capital
Formation
Infrared Energy
Radiated to
Space
Capital,
Labor,
Technology
Human
Economy,
Society
High-Entropy
Resources Pollutant
Stocks
(Wastes)
Necessary Conditions for a
Sustainable World
1. Renewable resources
can be used no faster than the rate at
which they regenerate.
2. Pollution and wastes
can be emitted no faster than natural
systems can absorb them, recycle them,
or render them harmless.
3. Nonrenewable resources
can be used no faster than renewable
substitutes for them can be introduced.
Source: Herman Daly
1. Renewable resources
can be used no faster than the rate at which they regenerate.
Regeneration
Resource
Available
Consumption
2. Pollution and wastes
can be emitted no faster than natural systems can absorb
them, recycle them, or render them harmless.
Waste
Generation
Pollution,
Waste
Recycling,
Decay
3. Nonrenewable resources
can be used no faster than renewable substitutes can be
introduced.
Resource
Available
Consumption
Example:
Earth’s Energy Balance
and Climate Change
Atmospheric CO2 (ppmv)
380
360
Atmospheric [CO2], ppmv
340
320
300
280
1850
CO2 Emissions
1900
CO2 in
Atmosphere
1950
2000
CO2 Removal
Average Surface
Temperature
+
Heat Stored
at Earth's
Surface
Energy from Sun
(Insolation)
-
Energy
Radiated to
Space
World Population Growth
.
February 2008:
6.65
Billion
6
Billion People
Average Growth Rate:
1900 - 1950: 0.86%/year (doubling time ! 80 years)
1950 - 1997: 1.76%/year (doubling time ! 40 years)
6
4
4
2
2
Upper Bound
0
1900
2000
Lower Bound
0
0
400
800
1200
1600
2000
Net Increase today: ≈ 77 million/year
Real Gross World Product, 1950-2004
Ave Growth Rate ≈ 3.5%/year
Doubling Time ≈ 20 years
At that rate, in 100 years GWP 32 times larger
Possible Futures
Fluctuation
around
equilibrium
Human
Activity
Overshoot and decline
S-shaped Growth:
Smooth, gradual transition
to equilibrium
Time
How will growth end?
Growth in human activity cannot continue forever
on a finite planet.
How will we make the transition?
Voluntarily or involuntarily?
Smoothly & peacefully or catastrophically?
With what population?
What standard of living?
What quality of life?
What degree of equity and social justice?
What role for nature, other species?
IPAT
Impact = Population * Affluence * Technology
Example:
CO2
= Population * Income * Emissions
Emissions
Capita
Dollar
Tons
year
=
People
* $/Year * Tons
Person
$
2
Billion Tons CO /Year
35
Impact
=
World Carbon Emissions
30
From Fossil Fuel Use
25
20
15
10
5
0 Source: DOE EIA
1980
1985
1990
7
1995
2000
2005
2010
2005
2010
World Population
Billion
6
Population
5
4 Source: US Census Bureau
1980
1985
1990
1995
6000
1990 $/Year/Person
*
Affluence
5000
4000
3000
2000
2
Tons CO /Thousand Real $
50
1985
1990
1995
2000
Impact
=
Carbon Intensity of the Economy
0.5
0.0 Source: DOE EIA
1980
1985
1990
1995
2000
From Fossil Fuel Use
20
10
0
1980
10
1990
2000
2010
2020
2030
2040
2050
2040
2050
World Population
Billion
7
6
1990 $/Year/Person
4 Source: US Census Bureau
1980 1990 2000 2010
10000
2020
2030
8000
6000
4000
World Average Income/Person
2000
2
Tons CO /Thousand Real $
2010
Emissions required
to stabilize [CO2] at
≈ 450-500 ppm
30
5
*
Technology
2005
World Carbon Emissions
8
*
Affluence
2010
1.0
40
9
Population
2005
1.5
2
Billion Tons CO /Year
World Average Income/Person
1000
0
1980
*
Technology
2000
0
1980
1.5
1990
2000
2010
2020
2030
2040
2050
Carbon Intensity of the Economy
1.0
0.5
0.0 Assumes decline at historical average (-1.1%/year)
1980 1990 2000 2010 2020 2030
2040
2050
How will we achieve sustainability?
• Better Technology?
• Lower Consumption?
• Lower Population?
• Huge technical, economic, political,
social and ethical issues for each
• All options linked by intricate feedbacks
Sweden
50
40
CBR
10
Population
30
20
8
6
CDR
4
10
2
0
1750
1800
1850
1900
1950
Population (millions)
Crude Birth Rate, Crude Death Rate
(per thousand)
Demographic Transition: Early Industrializer
0
2000
Before industrialization: High Death and Birth Rates -> Slow pop growth
During transition: Death rates fall faster than birth rates -> Rapid growth
After Transition: Low Death and Birth rates -> Slow, no, or even negative growth
Egypt
50
60
CBR
50
40
40
30
CDR
30
20
20
10
10
Population
0
1750
1800
1850
1900
1950
Population (Millions)
0
2000
Much faster drop in Death Rate; Same slow decline in Birth Rate.
Result: Faster population growth to higher level before transition complete.
Population Inertia
World
80+
Male
Female
70-74
60-64
50-54
Age
Crude Birth Rate, Crude Death Rate
(per thousand)
Demographic Transition: Later Industrializer
40-44
30-34
20-24
10-14
0-4
-400 -300 -200 -100 0
100 200 300 400
Population (millions)
9.4≈B6 B
World Age Structure 2050:
1998:
Age
World
80+
75-79
70-74
65-69
60-64
55-59
50-54
45-49
40-44
35-39
30-34
25-29
20-24
15-19
10-14
5-9
0-4
-400
Male
-300
Female
-200
-100
0
100
Population (millions)
200
300
400
Age
Brazil
80+
75-79
70-74
65-69
60-64
55-59
50-54
45-49
40-44
35-39
30-34
25-29
20-24
15-19
10-14
05-09
00-04
-10
Male
Female
-5
0
Population (millions)
5
10
Human Ecological Footprint
Ecological footprint (number of planet Earths)
1.5 1.5
Number of Earths Used by Humanity
1.0
0.5
0 0.0
61 964 967 970 973 976 979 982 985 988 991 994 997 000 003
1 1
1 1 1
1 1 1 1
1 1 1 2
2
19
1960
2005
Image by MIT OpenCourseWare. Adapted from Figure 1 in Wackernagel, et al. "Tracking the
Ecological Overshoot of the Human Economy." PNAS 99, no. 14 (2002): 9266-9271.
Footprint and Biocapacity (Carrying Capacity)
4.0 4.0
Global hectares per person
3.5
Biocapacity
3.0
2.5
2.0
1.5
1.0
Number of Earths
Used by Humanity
0.5
0 0.0
61 964 967 970 973 976 979 982 985 988 991 994 997 000 003
1 1 1 1 1 1 1 1 1 1 1 1 2 2
19
1960
2005
Image by MIT OpenCourseWare.
Ecological Footprint by Region
Courtesy of Jerrad Pierce. Used with permission.
S-Lab Spring 2008 Footprints
CATEGORY (Now)
FOOD
MOBILITY
SHELTER
GOODS/SERVICES
TOTAL FOOTPRINT
IF EVERYONE LIVED LIKE YOU,
WE WOULD NEED THIS MANY
PLANETS.
CATEGORY (Future)
FOOD
MOBILITY
SHELTER
GOODS/SERVICES
TOTAL FOOTPRINT
IF EVERYONE LIVED LIKE YOU,
WE WOULD NEED THIS MANY
PLANETS.
Low
1.00
1.00
1.00
2.00
9.00
Median
Mean
5.00
4.87
2.00
3.35
4.00
4.60
5.00
6.29
17.00
19.22
High
7.00
9.00
13.00
17.00
42.00
2.00
4.00
4.38
9.00
1.00
1.00
4.00
4.00
4.00
3.00
6.00
17.00
3.77
3.92
3.48
6.27
17.52
7.00
8.00
9.00
18.00
40.00
1.00
4.50
4.54
10.00
My Footprint: No Flying, 2.4; With Flying, 4.7
How much is enough?
How much would you need to spend each year to be happy? That is, how much
consumption would be enough to satisfy you?
Consumption spending here means expenditure to provide for the lifestyle you wish to
have, including food, clothing, shelter, travel, entertainment, and all other expenditures
on goods and services.
Consumption does not include charitable giving, but only what you spend on yourself
and your immediate family.
Consumption does not include saving or investment (for example to build future
income for retirement).
Consumption does not include payment of income taxes, but only the cost of the goods
and services you purchase.
Choose one of the following options:
A.
$
per year is enough.
B.
At least $
but more is always better.
per year,
How much is enough?
S-Lab Students Spring 2008
Class Average
- 1yr MBA
- 2yr MBA
- 1yr LFM
- 2yr LFM
- Fellows
- non-Sloan
$
$
$
$
$
$
$
Low
5,000
20,000
30,000
5,000
40,000
50,000
50,000
$
$
$
$
$
$
$
Median
60,000
60,000
50,000
50,000
77,500
165,000
50,000
$
$
$
$
$
$
$
Mean
102,542
100,478
104,000
62,571
98,750
170,000
62,000
GDP/Capita (PPP$/capita, 2004)
US
High Human Development Nations
World
Low Human Development Nations
$39,676
$26,568
$8,838
$1,113
(source:UNDP Human Development Report 2006; http://hdr.undp.org/statistics/data/)
More is always better: 58%
$
$
$
$
$
$
$
High
750,000
750,000
500,000
200,000
200,000
300,000
100,000
Class Mean/
Average
2.62
2.57
3.91
3.86
11.8
11.60
93.4
92.13
Our global civilization is not sustainable
• We depend on nonrenewable resources
• We consume renewable resources faster
than they regenerate
• We generate wastes faster than they can
be absorbed and rendered harmless
• We have pushed the ecosystems of the
planet into new regimes in which we have
no experience and do not understand
Growth Is Ending
• Growth is rapidly deepening our
unsustainability
• Population (but demographic transition)
• Economic growth
• Growth will stop.
• Question is not if, but how, when;
• Voluntarily and peacefully or involuntarily and
convulsively?
Innovation,Technology & Markets
• Powerfully increase environmental degradation
– By enabling growth
– Through unanticipated side effects
• Essential in creating a sustainable world
– Moderating our impact on the global carrying
capacity
– Repairing the damage we’ve already done
BUT
There is no purely technological solution to the
challenge of creating a sustainable society.
Next Time
What can we do?
What are the barriers to action?
• Please read:
– Repenning and Sterman (2001) Nobody ever gets credit for fixing
problems that never happened.
– Repenning et al. (2001) Past the Tipping Point: The Persistence of
Firefighting in Product Development.
– In Many Communities, It’s Not Easy Going Green,
New York Times 7 Feb 2008 (on the MIT server) ***NEW***
• Please think about the following questions:
– Have you ever worked for an “overloaded” organization that was stuck
in the “firefighting trap”? Why were you stuck? Did the organization
recover? If so, how?
– What are the major barriers to “going green” inside a for profit
corporation? How can they best be overcome?